Abstract: A tool for roughening a borehole surface. The tool includes a coupling portion for clamping the tool in a drilling machine; and a tool head for machining the borehole surface, where the tool head comprises a cutter that is circumferentially disposed on the tool head, and where the tool head has at least one slit, which passes through from one side to the other and which, starting from an end face of the tool head, and extends axially along a longitudinal axis of the tool.

Abstract: A tool for roughening a borehole surface. The tool includes a coupling portion for clamping the tool in a drilling machine; and a tool head for machining the borehole surface, where the tool head has an outer shell surface on which a cutter protrudes laterally from the shell surface, and where the outer shell surface has a camber along the longitudinal direction of the tool.

Abstract: A tool for roughening a borehole surface. The tool includes a coupling portion for clamping the tool in a drilling machine; and a tool head for machining the borehole surface, where the tool head comprises a cutter that is circumferentially disposed on the tool head, and where the tool head has at least one slit, which passes through from one side to the other and which, starting from an end face of the tool head, and extends axially along a longitudinal axis of the tool.

Abstract: A heat exchanger arrangement is made available for heating an area of a vehicle which is to be heated, having: a first heat exchanger element for transmitting waste heat from at least one vehicle electrical component to be cooled to air, and a second heat exchanger element for transmitting heat from at least one vehicle heating device to air. The first heat exchanger element and the second heat exchanger element are arranged in such a way that air (L) to be heated is successively applied to them.

Abstract: The invention relates to a motor vehicle cooling system, comprising a first cooling circuit, in which a coolant can be circulated, at least one electrical component of the vehicle, which is integrated in the first cooling circuit and is to be cooled, wherein the electrical component can be cooled by means of a coolant that can be circulated in the first cooling circuit, a refrigeration system, which is designed to provide cooling capacity, and a refrigerant-coolant heat exchanger, which is designed to transfer the cooling capacity provided by the refrigeration system to the coolant. A first coolant-air heat exchanger for cooling air for a vehicle interior is arranged in the first cooling circuit.

Abstract: A heat exchanger arrangement is made available for heating an area of a vehicle which is to be heated, having: a first heat exchanger element for transmitting waste heat from at least one vehicle electrical component to be cooled to air, and a second heat exchanger element for transmitting heat from at least one vehicle heating device to air. The first heat exchanger element and the second heat exchanger element are arranged in such a way that air (L) to be heated is successively applied to them.

Abstract: A process for starting a supplementary direct injection vehicle heater (10) with the following steps: detecting a starting signal (14) which is independent of the ignition process of the internal combustion engine (12), initiating measures to prepare for heating operation of the supplementary direct injection vehicle heater (10) when the starting signal (14) has appeared, and initiation of heating operation of the supplementary direct injection vehicle heater (10) when the internal combustion engine (12) is being started.